At this juncture, you may want to take a look at that
flow chart that I began our discussion with.
Do not lose sight of what we are trying to accomplish.
Our objective for that flow chart was to take a normal cell,
and then upon exposure various elements such as
chemicals that I walked you through including arsenics
such as chromium, such as nitrosamines so on and
so forth. The patient may develop a cancer
or if the patient is being exposed to certain viruses
here may develop cancer. Let's talk about HPV now.
Our topic is a DNA virus that the patient has been exposed
to and, he or she, develops cancer. Now HPV is a big deal.
Listen. With HPV you should be thinking about
sexually transmitted infection right, STI.
With HPV could be male or female put them both together.
And with HPV you should be thinking about the higher strains
not the lower. My topic is cancer. HPV 16,18,31 and 33.
And with HPV, in a female you begin with the following.
There might be vulva issues. So there might be squamous
cell cancer of the vulva. You keep going.
There might be issues within the vagina and in the cervix.
Would you tell me the part of the cervix that's facing you.
Meaning, facing you as a clinician when you do a pelvic exam.
That's the exocervix. What kind of cells is your exocervix?
Squamous. There you are in the transformation zone. Are you
there? Put yourself in the cervix, the transformation zone.
That which is facing the external world, exocervix is squamous.
That which is facing the uterus, endocervix is the columnar.
That's your transformation zone. Now you tell me quickly what is
it within the vagina that allows for the cells to remain squamous?
The decreased pH. What is the bacteria that remains within the
vagina that provides that type of acidic environment?
Lactobillus. Keep all that in mind because with HPV, 85% of
the time if the patient. Cervical cancer, where
is your patient most likely coming from? Developed or developing
countries? Good. Developing countries. 85% of the time
if you are in the transformation zone, the virus has a choice of
either becoming a adenocarcinoma or a squamous cell cancer.
85% of the time what is it going to choose? Squamous. Not only
that. With HPV maybe you have a couple that practices oral sex
and felatio so on and so forth. So there is every possibility
that HPV might enter the head and the neck. May result in
head and neck cancer. Guess what kind. Squamous. Now unbelieveably
you've learned in Immunology that you even have a vaccination for this
and it's called Gardasil. You are guarding against squamous
intra epithelial lesion. Where? Vulva, cervix, head and neck.
Is'nt that amazing. That you actually have a vaccine that may
prevent certain cancers from taking place. And then molecularly,
if you remember from micro, with HPV these strains contain E6
and E7. What do they do? Knock out the tumor suppressor gene
p53 and what's the other one? Rb. E6, E7 respectively. HPV, you
should know everything about HPV. What about the lower strain?
Condyloma Acuminata. What? Remember warts? That's your condyloma
acuminata. Know everything about HPV. Low strain, high strain.
Our topic, high strain. Alright, let's move on to EBV. EBV is
all over the place. Oh my goodness. Usually infects B-cells.
And if it's B-cells then what kind of CD are you looking for?
Good. CD 19,20,21. You should be focusing upon 21.
These are epithelial cells of nasopharynx. Nasopharynx, CD 21.
So if that's the case, is it possible that EBV might give rise to
nasopharyngeal cancer. Sure. Who's your population? Far east.
Japan and company. Our topic with EBV, associated highly with
Burkitt lymphoma. Translocation 8,14. t(8;14). By the
time we are done with our discussion of cancer
we will have gone through three major translocation
that contains 14. t(8;14), t(14;18), t(11;14).
Once again, t(8;14) Burkitt. t(14;18) Follicular.
t(11;14) I'm sorry, what? Good. Mantle cell.
Burkitt lymphoma. Specifically what if I give you a African
American boy. The boards will give you an African American boy.
Actually not even African American, literally from Africa, a child.
Where is Burkitt lymphoma affecting that African child? Mandible.
That's the one EBV is associated with more so. We call that the
endemic type. The non-endemic type, when we'll come to that
well, that will be the North American type, sporadic. Not so much
with EBV. B-cell lymphoma in immunocompromised. Hodgkin's big time.
The most common Hodgkin is not mixed cellularity. The
most common Hodgkin's would be the sclerosing type.
Also associated with EBV. Mixed cellularity as well.
What do you have to find pathologically, on biopsy,
to diagnose Hodgkin's. Without this you cannot call it
Hodgkin's. Reed?Sternberg cell. What is it?
It's a B-cell. It's a lymphoma. And nasopharyngeal. We began
talking about EBV and CD 21. Population here, far east.
Our topic is DNA viruses. So far, HPV, EBV then you have
Hepatitis B. Why is there no Hepatitis C here?
Because Hepatitis C is a RNA virus. So next when we talk
about RNA, we'll talk about Hepatitis C. Hepatitis B,
could be associated with chronicity, could be associated
with hepatocellular carcinoma of the liver.
RNA viruses that are important for you of developing
cancer. Whenever you think about hepatitis C
you should be thinking about chronicity. Hence
associated with hepatocellular carcinoma.
Then you have an interesting one here. It's called
HTLV-1. Human T-cell Lymphotrophic virus 1.
You focus upon the letter 'T'. HTLV virus 1 may give
rise to T-cell leukaemia/lymphoma. The gene here
that you will have to know is Tax. 'T'. HTLV 1.
Adult T-cell leukaemia/lymphoma. Tax.
Know this three for your step, you will be in good shape.
These are important RNA viruses. There are a bunch more.
But at least know this two associated with cancer. Bacteria associated
with cancer. Obviously this bring us to H.pylori. Helicobacter Pylori.
Helicobacter Pylori loves to live either in the antrum of the
stomach or it loves to live in the first part of the duodenum.
So, right around here right. In that area. The antrum and the
first part of the duodenum. H.pylori, you talked about urease
you know that it produces a forcefield. This thing is like a
superhero. But, it actually a supervillain, isn't it.
It creates a forcefield composed of alkaline. H.pylori. And at some
point with H.pylori it might give rise to a gastric adenocarcinoma.
And that's called intestinal type. And Helicobacter pylori might
then give rise to a second gastric cancer here and it's called
a MALToma (Mucuous associated lymphoid tissue), welcome to a
B-cell type. Why am I emphasizing B? Because in the gut,
in the GI system, if it's any type of lymphoma that the
patient is going to develop it is going to a B-cell.
A extranodal Non-Hodgkin's lymphoma, we
call this a diffuse large B-cell lymphoma.
Can be reversed with treatment. That is unbelievable isn't it.
The fact that you can actually treat a cancer by giving
H.pylori. Excuse me, you can treat a cancer by treating
H.pylori. Antibiotics, kills off the cancer.
Of course the boards will love this. And you're thinking
about drugs. Such as H2-blocker, maybe your clarithromycin,
antibiotic bismuth is in there as well. And it's important
that we pay attention to the management when the time is right.
You also have a PPI as well.